10.
API Resources • Extensive list of resources covering many data types• Each resource supports a variety of sub-resources – Usually linked to other resources

11.
API Level of Detail • Supports different levels of detail• Allows clients to trade- off detail for speed• Good for mobile apps

12.
API Caching & Storage • Caching is enabled at resource level• The API supports ETags – Every request returns an ETag in the header – With If-None-Match, supports web caching• We also abuse ETags to support persistent references to collections• An ETag can refer to other ETags recursively – Allows clients to create and store arbitrarily complex collections• Not permanent, not infinite!